The invention relates to an electromotive dual drive for an adjustment of two different furniture parts of a piece of furniture having two drive units, each of which comprises a drive motor, a transmission and a spindle drive having respective a spindle and acting on an output member. Both drive units are arranged one behind the other in a common housing in the longitudinal direction of the housing. Shaft holders for a respective pivot shaft of the furniture, on which a respective output member acts, are formed on both end sections of the housing which are mutually opposite in the longitudinal direction.
Such electromotive dual drives are used, for example, in order to be able to adjust the head part and the foot part of a slatted frame in an electromotive manner. They can easily be mounted on the furniture, e.g. the aforementioned slatted frame of a bed, by inserting in each case one pivot shaft of the furniture into one of the shaft holders. For this purpose, the shaft holders are usually provided with cover slides, which can be removed in order to be able to insert the pivot shaft into the shaft holder with a pivot lever. After repositioning the cover slides, the entire dual drive is fixed to the shafts. The drive units act independently of one another via their spindle drive and the output member on the respective pivot lever for adjusting the furniture parts.
Such a dual drive is known, for example, from the printed publication EP 1 266 439 B1. In this dual drive, an elongated common housing for the dual drive is provided, wherein both drive units are constructed in a substantially mirror-image manner with respect to a mirror plane which extends perpendicularly to the longitudinal direction of extension centrally through the housing of the dual drive. The drive motors of both drive units lie adjacent to one another in a central section of the housing, wherein the drive spindles face to the outside in alignment with each other. In the respective end section of the dual drive, the output members, which are designed as pressure plates, act on pivot levers of inserted pivot shafts.
In the longitudinal direction, the housing of the dual drive of the printed publication EP 1 266 439 B1 is divided into several sections by this arrangement of the drive units. In addition to the outer end sections through which the pivot shafts extend and in which the pivot levers lie, three sections can be subdivided: a section lying between the motors or reduction gears assigned to them, as well as a respective section located in the region of the spindles. Each of these sections provides the possibility to accommodate electrical and/or electronic components of the electromotive drive in the housing.
In such a design of known dual drives, a control board of the electromotive drive is usually arranged between the motors, and a further circuit board is provided in the area of the spindles, on which end position switches are arranged which are actuated by the output member. If an integrated power supply unit is provided, the transformer of such a power supply unit preferably also finds its place in the area between the motors. A disadvantage of the subdivision of the available space into several sections is the increased production complexity, resulting from the necessity of having to fix several circuit boards in the housing and having to wire them together.
In addition, the described construction is disadvantageous in view of the space requirement of the dual drive during shipping. In the lateral direction, i.e. in the direction of the pivot shafts, the housing is usually formed in a narrow way. The drive motors have an axis of rotation which is parallel to the pivot shafts, wherein the motors project laterally beyond the remaining width of the housing. Motor covers (motor domes) are arranged in the region of the motors in order to accommodate or cover the protruding motors. Both motors face to the same side in order to avoid increasing the lateral projection of the housing even further. If the double drives lie side by side at the same height during dispatch, they need a stacking width which corresponds to their width in the area of the motors. If the motors are rotated in such a way that two respective dual drives with their motors are orientated toward one another, they must be displaced in their longitudinal direction in order to be able to be arranged in a space-saving manner with respect to their width. This arrangement, which is more effective with regard to the width, then leads to an increased space requirement in the longitudinal direction of the drives. The arrangement of two drives which is offset in the longitudinal direction is also disadvantageous with regard to the size of the packaging in the longitudinal direction since the dual drives in the longitudinal direction already have an unwieldy length. Furthermore, it is desirable to use standardized packaging sizes, e.g. on the basis of euro palettes. An arrangement with a significant offset in the longitudinal direction can prevent the use of euro palettes depending on the length of the dual drives.
An electromotive drive is known from the printed publication DE 20 2013 101 521 U1, in which troughs are formed in the housing, so that supplied additional components, such as a remote control for the electromotive drive for example, can be arranged in this trough without them protruding laterally beyond the cover of the motors. In this way, the free space remaining between two dual drives, which is caused by the protruding motor covers, can be used sensibly during the packing and dispatch of the dual drive. However, the fundamental problem still remains in that the width during packaging is essentially determined by the width of the housing in the region of the motors.